@article{fdi:010080547,
  title = {{L}inking magmatic processes and magma chemistry during the post-glacial to recent explosive eruptions of {U}binas volcano (southern {P}eru)},
  author = {{S}amaniego, {P}ablo and {R}ivera, {M}. and {M}anrique, {N}. and {S}chiavi, {F}. and {N}auret, {F}. and {L}iorzou, {C}. and {A}ncellin, {M}. {A}.},
  editor = {},
  language = {{ENG}},
  abstract = {{U}nderstanding the links between the magma differentiation processes, the magma plumbing system and the magma composition at arc volcanoes is of paramount importance for volcanic hazard assessment. {I}n this work we focus on the post-glacial, {H}olocene, historical, and recent eruption products of {U}binas volcano ({P}eru), which display an overall decrease in silica content from the older, plinian ({VEI} 3-5), rhyolitic eruptions (69-71 wt% {S}i{O}2) to the historical and recent (2006-2009, 2013-2017), vulcanian ({VEI} 1-2) basaltic andesitic eruptions (55-57 wt% {S}i{O}2). {B}ased on a comprehensive study of the major and trace elements and the {S}r-{N}d{P}b isotopes, we conclude that this temporal pattern reflects the evolution of the {U}binas magmas in the middle-to-upper crust by a coupled {A}ssimilation-{F}ractional {C}rystallization ({AFC}) process involving a cumulate composed of plagioclase, amphibole, clinopyroxene, orthopyroxene and {F}e-{T}i oxides, with minor amounts of olivine and biotite at the mafic and felsic end-members, respectively. {U}pper crustal assimilation is limited to 5-8 vol%, but the overall radiogenic {S}r-{N}d-{P}b signature of the {U}binas magmas requires a larger crustal component, which must therefore occur at middle to lower crustal depths. {T}he petrology of the {U}binas magmas also points to an overall increase in {P}-{T} conditions: the large {H}olocene dacitic and rhyolitic eruptions record temperatures ranging from 800 to 850 degrees {C} and pressures in the range of 200-400 {MP}a, whereas the historical and recent (2006-2009, 2013-2017) basaltic andesitic eruptions provide higher temperatures and pressures (1000 degrees {C}, >300-400 {MP}a). {O}verall, the thermo-barometry, phase equilibrium and geochemical constraints allow us to pro pose the existence of a middle-to-upper crust magma column composed of a highly crystalline magma mush containing batches of liquid magma, which seems to be continually recharged from deeper levels. {O}n the basis of the petrological nature of the historical basaltic andesitic eruptions (1667 {CE}, 2006-2009, 2013-2017), we postulate that during the last centuries, {U}binas experienced a recharge-dominated process, with no evidence for a rejuvenation of the silica-rich reservoir that fed the large {H}olocene dacitic to rhyolitic eruptions. {T}his study highlights the importance of detailed petrological studies of {H}olocene sequences at explosive arc volcanoes in order to constrain the magmatic processes and conditions that control large explosive eruptions.},
  keywords = {{U}binas ; {P}eru ; {A}rc volcanoes ; {R}echarge ; {T}hermobarometry ; {M}agma plumbing system ; {PEROU} ; {UBINAS} {VOLCAN}},
  booktitle = {},
  journal = {{J}ournal of {V}olcanology and {G}eothermal {R}esearch},
  volume = {407},
  numero = {},
  pages = {107095 [25 ]},
  ISSN = {0377-0273},
  year = {2020},
  DOI = {10.1016/j.jvolgeores.2020.107095},
  URL = {https://www.documentation.ird.fr/hor/fdi:010080547},
}